(William McKinley High School was having their senior prom tonight. Santana Lopez and Quinn Fabray have both been running campaigns for prom queen, along with senior class president Brittany Pierce and quarterback Finn Hudson. Sam Evans and Mercedes Jones have been coming closer together in their relationship. Blaine Anderson tries to get over his gel addiction as the prom day comes closer. Rachel Berry is upset when she finds out that Finn and Quinn are running for prom king and queen. At the start of the prom, Brittany performs link by Britney Spears. Everyone is either entering, dancing...